This invention relates to a portable pneumatic air jet cleaning device which operates to clean crevices and the like by directing streams of pressurized air along a surface to be cleaned so as to remove loose debris, snow, and the like. The present invention is particularly adapted for pneumatic removal of snow between closely spaced-apart railroad rails and especially for cleaning between portions of a railroad switch which are susceptible to becoming jammed as a result of snow packed between the switch rails.
The need for a device which can clean crevices and the like has long been recognized, and several devices have been constructed to remove debris from various hard-to-reach crevices. For example, U.S. Pat. No. 2,320,964, issued June 1, 1943, to Yates, discloses a safety air nozzle which expels a highly pressurized stream of air from an elongated nozzle and a second, conical skirt of air surrounding the elongated nozzle.
Another attempt at providing an air nozzle for cleaning debris from inaccessible locations is shown in U.S. Pat. No. 3,117,726 issued Jan. 14, 1964, to Schoberg. The Schoberg patent discloses a nozzle which also directs a concentrated stream of air through a main port with this main stream being surrounded by a conical skirt of pressurized air from a concentric outlet to prevent debris from blowing back onto the operator. This skirt of air is outwardly directed by means of the sidewalls of the central nozzle portion of the apparatus.
However, the applicant has tried these prior art and other experimental devices, and none of the prior art known to the applicant discloses a system adequate for efficient removal of snow between the rails of a railroad switching track. In constructions having a skirt of air similar to the teachings of the patents to Yates and Schoberg, the conical skirt causes the snow to be blown back into the crevice already cleaned so that the rails still are mechanically blocked or jammed by snow and are thus prevented from adequately switching from one mode to another. Further, the force generated by these systems of air pressure jets has not proven sufficient to blow away large masses of snow which accumulate on the rails of a railroad switch yard in climates where heavy and blowing snow is common. There is therefore the need for a portable air jet cleaning device which has sufficient power to actually lift large quantities of chunks of snow, debris, or the like, and to propel it away from a crevice in a manner which prevents the material from refilling the crevice as the device is moved therealong.